gistfile1.php

<?php
/**
 * Stores the information submitted during registration
 *
 */
function pw_rcp_save_user_fields_on_register( $posted, $user_id ) {

	if( ! empty( $posted['rcp_profession'] ) ) {
		update_user_meta( $user_id, 'rcp_profession', sanitize_text_field( $posted['rcp_profession'] ) );
	}

	if( ! empty( $posted['rcp_location'] ) ) {
		update_user_meta( $user_id, 'rcp_location', sanitize_text_field( $posted['rcp_location'] ) );
	}

}
add_action( 'rcp_form_processing', 'pw_rcp_save_user_fields_on_register', 10, 2 );